Already on edge, Southwestern Ontario pork producers got another shot of bad news on the weekend after a highly contagious piglet-killing disease that made its Canadian debut in the London area was detected on a hog farm more than 200 kilometres away.

Officials have confirmed five cases of porcine epidemic diarrhea (PED) in a 10-day period — four of them in Southwestern Ontario — with the latest case found north of Toronto in Simcoe County, the Ontario Agriculture and Food Ministry said.

News of the disease creeping outside Ontario’s main hog belt raised fears the $1-billion-a-year Ontario hog industry could go down the same road as its counterpart in the United States, where PED has spread to 22 states since first being detected in May, killing as many as three million piglets and driving up pork prices.

“Everyone’s on high alert now,” said Huron County hog farmer Phil Dykstra. “And so when you see something that’s remotely suspicious, producers are calling their vet, they’re taking some swabs.”

Adding to the problem of containing the virus is the bitter cold winter gripping the region.

Not only does the virus have an indefinite life span in the cold, it’s also easily transferred through snow and slush, said Martin Misener, a veterinarian with the Ontario Swine Advisory Board.

“Biology beat us at this point. Now we just got to shift gears and really focus on reducing spread,” he said.

The disease has also been detected at an Ontario processing plant, assembly yard and a trucking yard.

Last week the federal government announced it will allow importation of a PED vaccine for use in pig herds as a precautionary measure.

Still in preliminary testing, vaccinated pigs have developed antibodies against the virus.

In a sign of farmers’ increased vigilance, there have been a number of suspected PED cases that have come back negative, said Susan Murray, a spokesperson for Ontario’s Agriculture and Food Ministry.

“There are other illnesses that can give pigs diarrhea and vomiting,” Murray said. “So we’ve actually had a number of negative tests for PED, so that’s good.”

The first Canadian case of PED was confirmed Jan. 22 at a farm in Middlesex County — one of the top pork producing counties in Ontario.

Two other cases were confirmed in Chatham-Kent and one in Norfolk County.